Circular knitting machine creels are bobbin frames in which a number of bobbins are arranged in a circle and in tiers above one another. Threads drawn off from the bobbins are fed to knitting machines. When threads are drawn off, fuzz is produced which collects on parts of the frame and on the floor and makes it necessary to clean the frame and floor area periodically. Unavoidably, fuzz collects on parts of the frame, and an accumulation often comes loose from the frame and is carried along by a thread. This can result in a fuzz accumulation being embedded in the stitches of the knitwear and perhaps lead to substandard knitwear. Embeddings of this type can usually be easily seen since there are bobbins of different colours on the bobbin frame.